Born to Run, Pt 2: It’s all in the toes
April 21, 2009 at 4:45 am
Around a year ago I posted a link to stories in the Harvard Gazette and from ABC News about the antropological argument that humans were, literally, born to run. We survived the hyenas, lions, and other scavengers of the African plane more than 2-3 million years ago by being able to outrun them — not with pure speed (cheetahs: 1, humans: 0), but over long distances, say some researchers.
Four-legged animals can move like missiles, but tall, two-legged creatures move like pogo sticks. To be fast and steady, you need a head that oscillates up and down, but doesn’t pitch back and forth or bobble from side to side. The nuchal ligament is one of several features that allowed early humans to run with steady heads held high.
There are some skeptics, however, to the theory that endurance running among early humans is the “missing link” in tracing our evolution. One researcher notes, “Early female humans likely did not participate in long hunts, but stayed behind to care for the young. If this is the case, why would women also have evolved to be good long-distance runners”
And just because we can run long distances does not necessarily mean we evolved specifically because of this ability.
Yet as we toast tonight to the nearly 25,000 runners who participated in the 113th Boston Marathon on Monday, it seems fitting to revisit the topic of running and its role in human evolution.
And thanks to a new study on our toes (!), “the endurance running hypothesis may have legs.” From this fantastic article in SEED Magazine:
A handful of scientists think ultra-marathoners are using their bodies just as our hominid forbears once did, a theory known as the endurance running hypothesis (ER). ER proponents believe that being able to run for extended lengths of time is an adapted trait, most likely for obtaining food, and was the catalyst that forced Homo erectus to evolve from its apelike ancestors. Over time, the survival of the swift-footed shaped the anatomy of modern humans, giving us a body that is difficult to explain absent a marathoning past.
Our toes, for instance, are shorter and stubbier than those of nearly all other primates, including chimpanzees, a trait that has long been attributed to our committed bipedalism. But a study published in the March 1 issue of the Journal of Experimental Biology, by anthropologists Daniel Lieberman and Campbell Rolian, provides evidence that short toes make human feet exquisitely suited to substantial amounts of running. In tests where 15 subjects ran and walked on pressure-sensitive treadmills, Lieberman and Rolian found that toe length had no effect on walking. Yet when the subjects were running, an increase in toe length of just 20 percent doubled the amount of mechanical work, meaning that the longer-toed subjects required more metabolic energy, and each footfall produced more shock.
Read the entire article, “The Running Man, Revisited” by
Entry filed under: etc, play. Tags: 113th Boston Marathon, anthropology, biology, born to run, Boston Marathon, Campbell Rolian, Daniel Lieberman, early humans, Encino Man, endurance running, endurance running hypothesis, ER proponents, evolution, evolution of a runner, Homo erectus, humans, J. R. Atwood, Jason Atwood, Maywa Montenegro, missing link, nuchal ligament, outrun, research, runner, running, running man, SEED Magazine, toes, trail running, ultramarathon.